Cummins/Onan 12.5 RDJC / 15.0 RDJC — Priming the Fuel System
Maintenance
For the Cummins/Onan 12.5 RDJC / 15.0 RDJC, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan 12.5 RDJC, Cummins/Onan 15.0 RDJC, Cummins/Onan RDJC
Procedure
- Check fuel level in fuel tank and open shutoff valve.
- Loosen the fuel filter-to-injection pump line at the injection pump fuel inlet fitting.
- Actuate the hand priming lever on the fuel transfer pump until fuel flows from the fitting.
- Crank the engine one revolution to permit hand priming if the pump lobe of the camshaft is up.
- Tighten the fuel line at the injection pump inlet.
- Actuate the hand priming lever several more times to prime the injection pump.
- Return the priming lever inward (disengaged position) to permit normal pump operation.
Full service-parts list: Cummins/Onan RDJC →
Source: Cummins/Onan operator's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.